Hi Chakradhara,
can you briefly explain what the use for such a requirement is?
The contract is used as fix agreement with the customer for materials wich agreed prices, surcharges etc.
So why you should made such an agreement for adummy material and call off the contract within a sales order with another material which is maybe also more expensive?
You also do not make a contract with IBM for a toaster but requesting later a powerbook.
Regardless the business background this is not possible with SAP standard.
What you are doing within the copy control or even users exits is another topic.
Regrettable I do not have a template for such a process.
Best regards
Patrick